When he pardoned Eddie Gallagher based on his Fox News lobbying, Trump sold out a dozen Navy SEALs who came forward and tried to do the right thing. But he’s just happy to get a new campaign surrogate: The men of Alpha Platoon, SEAL Team 7, described Chief Gallagher as “freaking evil” and “toxic” in videos not shown publicly before. The remarks are blistering testimony about their platoon chief, who was protected by Trump from punishment.

https://www.nytimes.com/2019/12/27/us/navy-seals-edward-gallagher-video.html?smtyp=cur&smid=tw-nytimes

Just a reminder that he knifed a kid who the Iraqis had turned over to us for medical attention: The boy shown in the video was the only IS fighter to survive a battle in Mosul in the spring of 2017, and he had a physique so slender that a wristwatch fit around his bicep. He was slightly wounded in the battle, Frank Sheridan, an Irish-born forensic pathologist, told the jurors. Afterwards Iraqis handed the boy over to the Navy Seals for medical care in a military compound. | Gallagher initially tended to the boy. Then according to seven members of the platoon, he stabbed him. One of them, Craig Miller, said he saw blood gush from the boy's jugular, a stream of liquid like the kind that one sees when a baby is "throwing up". Gallagher later texted his friends a photo of the dead boy: "Good story behind this," he wrote. "Got him with my hunting knife."
https://www.bbc.com/news/world-us-canada-48536760

He was also known for shooting at civilians
https://www.navytimes.com/news/your-navy/2019/06/22/witnesses-eddie-gallagher-shot-civilians-in-iraq/